KR101127412B1

KR101127412B1 - Touch panel having improved visibility and manufacturing method of the same

Info

Publication number: KR101127412B1
Application number: KR1020100036701A
Authority: KR
Inventors: 황현하
Original assignee: 이미지랩(주)
Priority date: 2010-04-21
Filing date: 2010-04-21
Publication date: 2012-03-26
Also published as: WO2011132851A2; WO2011132851A3; KR20110117317A

Abstract

The present invention relates to a touch panel having improved visibility and a method of manufacturing the same, and an object of the present invention is to remove an air gap region formed between an upper substrate and a lower substrate of a touch panel, and furthermore, to push a conductive ball due to touch pressure. The present invention provides a touch panel having improved visibility and a method of manufacturing the same, which can prevent a phenomenon and prevent a touch coordinate error.
The touch panel having improved visibility according to the present invention is a resistive touch panel having an upper substrate patterned with an upper contact electrode and a lower substrate patterned with a lower contact electrode, wherein one surface of any one of the upper substrate and the lower substrate is formed. The transparent fastening layer to which the conductive balls are fixed is laminated on the substrate, and one substrate on which the transparent fastening layer to which the conductive balls are fixed is laminated is bonded to the other substrate by the transparent adhesive layer. Touch panel.

Description

Touch panel with improved visibility and manufacturing method {TOUCH PANEL HAVING IMPROVED VISIBILITY AND MANUFACTURING METHOD OF THE SAME}

The present invention relates to a touch panel, and more particularly, to remove air gaps and conductive ball push phenomena between an upper substrate and a lower substrate of a resistive touch panel through a multilayer structure including a transparent fixing layer and a transparent adhesive layer. The present invention relates to a touch panel having improved visibility and a method of manufacturing the same.

With the development of mobile communication and electronic devices, electronic information terminals such as mobile phones, PDAs, and navigation systems have become more diverse and complex media providing means such as audio, video, wireless internet web browsers, etc. Is expanding. For this reason, a larger display screen is required within the limited size of the electronic information terminal, and thus a touch screen display device is in the spotlight.

In the touch screen display device, a touch panel is laminated on a display panel such as a liquid crystal display, a PDP, and the like, and when a user presses the screen while looking at the display device, a corresponding signal is output to display a desired screen.

As such, the touch screen display device has an advantage of saving space compared to the conventional key input method by integrating a screen and coordinate input means, and the electronic information terminal to which the touch screen display device is applied has a screen size and As user convenience can be further increased, the use of this method is increasing.

Types of touch panels include capacitive overlay, resistive overlay, and infrared beam. The resistive film currently widely adopted in Korea will be described. 1 is a cross-sectional view of a conventional resistive touch panel.

In the conventional resistive touch panel 10, the upper substrate 11, the upper contact electrode 13, the lower substrate 19, and the lower contact electrode 17 are bonded to each other by an adhesive 15 such as a double-sided tape. . Thus, as shown in FIG. 1, the air gap 300 is formed in the region except the edge junction, and a plurality of insulating dot spacers 21 are formed on the lower contact electrode 17 to prevent a contact error. As shown in FIG. 1, the conventional resistive touch panel 10 is diffusely reflected when external incident light 100 is incident by an air gap 300 formed between the upper substrate 11 and the lower substrate 19. 110 is generated, and the diffuse reflection 210 is generated even when the internal light 200 emitted from the display device is emitted to the outside. Such diffuse reflection lowers the transmittance and thus causes a problem of lowering the visibility of the output screen of the display device. In order to compensate for the decrease in transmittance due to the above-mentioned diffuse reflection, illuminance of the backlight unit may be increased. In this case, power consumption may increase.

In addition, since only the edge portions of the upper substrate 11 and the upper contact electrode 13 and the lower substrate 19 and the lower contact electrode 17 are coupled by an adhesive 15 such as a double-sided tape, the center portion and the edge portion of the screen The gap between the upper substrate 11 and the lower substrate 19 was not kept constant. In particular, the upper substrate of the touch panel should be formed of a transparent plastic material such as polyethylene resin (PET), which is usually transparent glass. The spacing irregularities occur more frequently than the use of the substrate, and deterioration of display characteristics such as Newton rings are generated frequently when the user presses the upper substrate.

In order to solve the above problems, in Korean Patent No. 10-0903419, which is registered by the same applicant as the present invention, as shown in Figure 2, the upper substrate and the lower substrate is entirely made of a transparent adhesive containing a conductive ball The structure in which the faces are joined is presented. However, according to the above known technology, a case in which the conductive ball flows without being fixed to the lower contact electrode may occur, which causes the following problem.

That is, when the upper substrate including the upper contact electrode is pressed, the conductive ball is pushed to the side by the user's touch pressure in the process of conducting contact with the lower contact electrode of the lower substrate through the conductive ball as a medium. In some cases, the lower electrode may be in contact or no contact may occur. In this case, a touch may be generated at a point different from a point desired by the user, thereby causing a malfunction of the display device as the wrong touch coordinate is recognized.

The present invention has been made to solve the above problems, an object of the present invention is to remove the air gap region formed between the upper substrate and the lower substrate of the touch panel, and furthermore the conductive ball push phenomenon by the touch pressure The present invention provides a touch panel having improved visibility and a method of manufacturing the same, which can prevent the touch coordinate error.

The purpose of the resistive touch panel having a patterned upper substrate patterned upper substrate and lower substrate patterned lower substrate, the conductive ball is fixed on one surface of any one of the upper substrate and the lower substrate The adhesion layer is laminated, and any one of the substrates on which the transparent adhesion layer to which the conductive balls are adhered is laminated may be achieved through a touch panel having improved visibility, wherein the other substrate is bonded by a transparent adhesive layer. .

The touch panel having improved visibility may include a first step of manufacturing an upper substrate having an upper contact electrode patterned on one surface and a lower substrate on which a lower contact electrode is patterned on one surface; A second step of laminating a transparent fixing layer having conductive balls fixed to one surface of one of the upper substrate and the lower substrate; A third step of forming a transparent adhesive layer stacked with a spacer on the transparent fixing layer to which the conductive balls are fixed; And a fourth step of bonding the upper substrate and the lower substrate.

According to the touch panel with improved visibility according to the present invention and a method of manufacturing the same, apart from the transparent adhesive layer, a touch action of the user is formed by forming a transparent fixing layer in which a portion of the conductive balls are mixed or attached to the conductive balls. There is a remarkable effect of preventing a touch error in which the conductive ball is pushed by an applied pressure and an undesired touch coordinate is recognized.

In addition, by applying a transparent adhesive layer containing a part of the conductive ball to the entire upper substrate and the lower substrate is adhered to the overall reflection by the air gap formed in the conventional resistive touch panel can minimize the reflection is improved visibility There is a noticeable effect.

In addition, in the conventional method of bonding only the edge portion, it is possible to significantly reduce the Newton ring phenomenon caused by the gap between the upper substrate and the lower substrate.

1 is a cross-sectional view of a conventional resistive touch panel.
2 is a cross-sectional view of a resistive touch panel to which a conventional transparent adhesive layer is applied.
3 is a process flowchart showing a manufacturing process sequence of the touch panel with improved visibility according to the present invention.
4 is a cross-sectional view of the touch panel with improved visibility according to the first embodiment of the present invention.
5 is a cross-sectional view of a touch panel with improved visibility according to a second embodiment of the present invention.
6 is a cross-sectional view of the touch panel with improved visibility according to a third embodiment of the present invention.
7 is a cross-sectional view of a touch panel with improved visibility according to a fourth embodiment of the present invention.
8 is a cross-sectional view of a touch panel with improved visibility according to a fifth embodiment of the present invention.
9 is a cross-sectional view of a touch panel with improved visibility according to a sixth embodiment of the present invention.
10 is a cross-sectional view of the touch panel with improved visibility according to the seventh embodiment of the present invention.
11 is a cross-sectional view of a touch panel with improved visibility according to an eighth embodiment of the present invention.

In particular, the touch panel having improved visibility according to the present invention includes a transparent adhesive layer for bonding the upper substrate and the lower substrate over the entire surface of the resistive touch panel, and a conductive ball for recognizing touch coordinates on one surface of the substrate. Through the multi-layer touch panel configuration including a transparent fixing layer fixed to the substrate, the air gap generated by the conventional bonding method can be eliminated, and the conductive ball push phenomenon due to the touch pressure can be prevented, thereby preventing touch coordinate error. The technical characteristics that can be presented.

Hereinafter, with reference to the accompanying drawings will be described in detail a preferred embodiment, advantages and features of the present invention.

4 is a cross-sectional view of the touch panel with improved visibility according to the first embodiment of the present invention.

Referring to FIG. 4, the touch panel according to the first embodiment of the present invention includes an upper substrate 11 on which the upper contact electrode 13 is pattern deposited and a lower substrate 19 on which the lower contact electrode 17 is pattern deposited. The conductive ball 30 has a structure that is bonded by an elastic or transparent transparent adhesive layer 25 is irregular or regularly mixed, the conductive ball 30 is part of the transparent fixing layer 40 in the form of a lower substrate It has the structure which was attached and fixed on 19.

The material of the upper substrate 11 is not particularly limited as long as the light transmittance is good at least. Examples of specific materials of the upper substrate 11 include engineering plastics such as polycarbonate-based, polyamide-based, and polyether-based, acryl-based, polyethylene telephthalate-based, polybutylene telephthalate-based, polystyrene-based, cellulose-based, and the like. It is preferable to use a resin having excellent transparency in the operating area. It is also possible to use tempered glass substrates or ordinary glass substrates which are advantageous in terms of strength.

Materials of the lower substrate 19 include polycarbonate-based, polyamide-based, polyether-based engineering plastics, acryl-based, polyethylene telephthalate-based, polybutylene telephthalate-based, polystyrene-based, cellulose-based, and the like. It is preferable to use a resin having excellent transparency in the operating area. It is also possible to use tempered glass substrates or ordinary glass substrates which are advantageous in terms of strength. In particular, since the lower substrate 19 also serves as a support for the touch panel, a thickness of less than 0.25 mm may cause a problem in durability, so it is preferable to use 0.25 mm or more. Furthermore, in the case of a so-called film-type touch panel, it is preferable to increase the thickness of the lower substrate 19. This is to prevent the touch panel from being curved by the load at the time of input. Of course, there may be a case in which the upper substrate 11 and the lower substrate 19 have the same thickness, and a PC (Polycarbonate) substrate having a thickness of 1.0 to 1.5 mm serving as a support function is provided under the lower substrate 19.

The upper contact electrode 13 and the lower contact electrode 17 are patterned on each surface of the upper substrate 11 and the lower substrate 19. The upper contact electrode 13 and the lower contact electrode 17 are preferably formed. Is composed of Indium Tin Oxide (ITO) or Antimon Tin Oxide (ATO), and is formed in an operation region (ie, a touch screen region) of one surface of a substrate.

On the non-active area (substrate edge) except for the operation area, the electrode wirings Ag are printed and electrically connected to the upper and lower contact electrodes 17. The electrode wirings are connected to the FPC through conductor pins. Flexible Printed Circuit (not shown), and the FPC is bonded to the lower substrate 19.

According to the first embodiment of the present invention, the transparent fixing layer 40 in which the conductive balls 30 are mixed is stacked on the lower substrate 19 on which the lower contact electrode 17 is formed.

When the user presses the upper substrate 11 of the touch panel, the conductive ball 30 conducts the conductive ball between the upper contact electrode 13 formed on the upper substrate 11 and the transparent electrode formed on the lower contact electrode 17. In this way, it is formed by a method such as carbon fiber (Carbon Fiber), metal (Ni, Solder) or Metal (Ni, Au) -Coated Polymer, the conductive ball of the metal-coated polymer (Metal-Coated Polymer) This is widely used. Metal-coated conductive balls are most widely used to produce Ni (0.1um) and Au (0.05um) in order to coat a polymer spacer core. The conductive ball 30 may be transparent, but may have an opaque property when a metal is coated on the surface. However, even if the conductive ball is opaque, since the density of the conductive ball present in the transparent adhesive is not so high, it does not significantly affect the overall transmittance.

The transparent fixing layer of the present invention is a structure for fixing the conductive balls 30 on the lower substrate 19 by laminating the lower contact electrode 17 on one surface of the patterned lower substrate 19. Has a light transmittance of at least 80% or more (preferably 90% or more) and a refractive index greater than that of air, and does not peel off from the lower contact electrode 17 formed on the lower panel 19 of the touch panel even upon repeated touches. When composed of a transparent adhesive having adhesion to adhesion (preferably 50 gf / in or more), both conductive adhesives and insulating adhesives as well as general transparent adhesives (for example, general adhesives or double-sided tapes) can be applied. Although not limited, preferably, the polymer-based liquid resin is UV-cured or thermoset to form a solid transparent fixing layer 40.

When the insulating polymer resin is applied as the transparent fixing agent, it is preferable to use a polymer resin pressure-sensitive adhesive having an optically transparent and larger refractive index than air, such as an acrylic copolymer, a silicone elastomer or an epoxy copolymer.

Acrylic copolymers that can be used can be broadly classified into UV polymerizable and UV crosslinkable. In the case of the UV polymerized acrylic copolymer pressure-sensitive adhesive, the composition concept of the optical radical polymerization type or the photocationic polymerization type is the same, and various additives may be mixed. The basic component is an oligomer, a monomer, a photopolymerization initiator, a filler having a small inorganic particle size, an adhesion improving agent, or the like.

In the radical photopolymerization type, the basic properties of the UV adhesive are determined by the structure of the oligomer. In general, the epoxy acrylate oligomer is excellent in heat resistance and chemical resistance, and the urethane acrylate oligomer is rich in flexibility and excellent in adhesion.

Silicone elastomers consist of a main component material that matches insulation, permeability and refractive index, a subcomponent material that controls adhesion and a curing agent. The main ingredient may be at least one selected from sticky silicate resins, siloxane polymers, dimethyl siloxanes, dimethylvinyl ternates, dimethylvinyl-based trimethyl silicas, and tetrasylene.

In addition, when the transparent adhesive is composed of a conductive adhesive, a conductive polymer material such as PEDOT may be used. PEDOT has a merit that the polymer absorption band is present in the infrared region (760 ~ 780nm) and has the advantage of having a transparent property in the visible light region can be used as a transparent fixing agent of the present invention that requires transparency.

In the touch panel having improved visibility according to the present invention, the conductive substrate 30 is fixed to the transparent fixing layer 40 formed by the above-described transparent fixing agent in such a manner that a part of the conductive ball 30 is included in the lower substrate 19. It is a main technical feature that it can be fixed to

Therefore, the touch panel of the present invention forms a layer including a part of the conductive ball 30 in the transparent fixing layer 40 on the lower substrate 19 through the following manufacturing method.

When the polymer resin material is applied as the transparent fixing agent, a plurality of conductive balls 30 are added to the liquid transparent fixing agent and mixed before forming the transparent transparent fixing layer 40 on the lower substrate 19. By stirring and evenly mixing the liquid transparent fixing agent containing the conductive balls 30, the conductive balls 30 may be sufficiently dispersed at a predetermined interval therebetween.

When the mixing and stirring process of the conductive ball 30 and the liquid resin is completed, it is applied to one surface of the lower substrate 19 on which the lower contact electrode 17 is formed and then solidified to form a coating layer. The UV curing or thermosetting method may be used, and as the thermosetting method, far-infrared heating may be used.

The transparent fixing layer in which the conductive balls are mixed is formed on the lower substrate 19 through the above-described process as shown in FIG. 4. As can be seen in the cross-sectional view of FIG. 4, the conductive ball 30 is maintained on the lower substrate 19 by the transparent fixing layer 40, but only a part of the volume of the conductive ball 30 is the transparent fixing layer. It is configured in the form coupled to 40.

That is, it is preferable that the transparent fixing layer 40 for fixing the conductive ball 30 of the present invention on the lower substrate 19 is formed to have a thickness at least smaller than the diameter of the conductive ball 30. When the thickness of the transparent fixing layer 40 is formed to be the same as or larger than the size of the conductive ball 30, the conductive ball 30 is configured to be completely contained in the transparent fixing layer 40, This is because a case in which the role of the conductive ball 30 for detecting touch coordinates may not be performed may occur. That is, when the upper contact electrode 13 of the upper substrate 11 is pressed with a finger or a stylus pen, the user is in contact with the lower contact electrode 17 of the lower substrate 19 via the conductive ball 30. The touched coordinates can be determined, because if the entire conductive ball 30 is buried in the transparent fixing layer 40, it may not be possible to perform such an electrical medium. The touch panel according to the first exemplary embodiment of the present invention used a conductive ball 30 having a diameter of 25 μm, and thus, the transparent fixing layer 40 is preferably formed to have a thickness of at least 25 μm.

In particular, when forming the transparent fixing layer 40 by applying a liquid polymer resin to cure, it is preferable to use a mixture of volatile solvent (Solvent) such as dichloromethane or methyl acetate in the liquid polymer resin Preferably, when the transparent fixing layer 40 is formed using the resin solution containing the volatile solvent, thickness control of the transparent fixing layer 40 is achieved through smooth surface leveling (ie, achieving a uniform thickness). There is an easy advantage.

The volatile solvent contained in the resin solution is easily evaporated and removed in the curing / drying process to finally form the transparent fixing layer 40 made of pure resin. Therefore, in the case where a volatile solvent is mixed and used in the liquid polymer resin, all the volatile solvents are evaporated and removed, so that the thickness of the finally formed solid content is smaller than the diameter of the conductive ball 30. It does not affect the role of.

In the touch panel according to the present invention, the transparent adhesive layer in which the conductive balls are mixed is laminated on one surface of the lower substrate 19, and the elastic adhesive layer 25 is elastically laminated thereon and is not included in the transparent adhesive. The non-conductive ball 30 has a structure included in the transparent adhesive layer 25.

The transparent adhesive layer 25 is used as a filler to be filled in the space between the upper substrate 11 and the lower substrate 19 of the touch panel, and a portion of the conductive ball 30 and the spacer 27 mixed therein is transparent. In addition, the film is insulating and has a gel characteristic that is adhered to the “transparent fixing layer mixed with conductive balls” stacked on the upper contact electrode 13 and the lower substrate 19 of the upper substrate 11.

The spacers 27 are mixed in the transparent adhesive layer 25 to maintain the upper and lower substrates 19 properly, and to support the upper substrate 11 when the upper substrate 11 is pressed. It is used to provide a restoring force so that smooth restoring is made when restoring after 11 is pressed. The spacer 27 may be formed of a polymer spacer core. The spacer 27 may use a ball spacer having a spherical ball shape, the diameter of which is equal to or smaller than the thickness of the transparent adhesive layer 25, and the conductive ball 30 may be formed of the spacer 27. It should be smaller than the diameter. In addition, in FIG. 4, an example in which the ball-shaped spacers 27 are mixed with the transparent adhesive layer 25 is illustrated. However, if the touch panel has a small size, a dot spacer may be used instead of the ball spacer.

The transparent adhesive layer 25 used in the present invention should be an electrical insulator, and the refractive index of the transparent adhesive layer 25 is less than 0.1 from the refractive index of the upper substrate 11 and the lower substrate 19 constituting the touch panel. It is preferable to configure so as to have, but more preferably configured to have the same refractive index.

The transparent adhesive layer 25 should be formed of a material that is optically transparent, has a refractive index greater than that of air, and has elastic properties. Preferably, a liquid polymer resin such as an acrylic copolymer, a silicone elastomer, or a transparent epoxy resin is used. It can form by hardening. When the liquid polymer resin is used as described above, the structure is similar to that of the case where an insulating liquid polymer resin is employed as the transparent fixing agent to form the transparent fixing layer 40, but there are differences in the following points. This will be described later.

In addition, the touch panel of the present invention has a laminated structure in which the transparent adhesive layer 40 is interposed between the upper and lower substrates 19 together with the transparent adhesive layer 25, such a transparent adhesive layer 40 and the transparent adhesive layer. Layer 25 may also be configured to have similar optical properties. Therefore, the amount of light reflected by the difference in refractive index at the interface between the transparent adhesive layer 40 and the transparent adhesive layer 25 can be minimized, but preferably configured to have a refractive index difference of 0.1 or less.

As described above, the touch panel having improved visibility according to the present invention is considered to have an optical property such as a difference in refractive index between the heterogeneous layers (that is, the transparent fixing layer and the transparent adhesive layer). The adhesive layer 25 is preferably composed of a similar material group. Therefore, the transparent adhesive layer 25 of the present invention is formed of a liquid polymer resin, the transparent adhesive layer 40 is also preferably used in the above-described transparent adhesive polymer polymer series, but is formed with the following detailed differences .

First, the transparent adhesive layer 25 is naturally compressed and pressed when pressed in response to a user's touch operation to conduct the conductive ball 30, and when the external force is removed, elastically restores again and the electrical contact of the conductive ball 30 is separated. Since the flexible flexibility and elasticity are important, it is preferable to form a Shore Hardness of "30 or less". In addition, in the event that a defect occurs in some touch electrodes, it is necessary to remove the upper substrate 11 and the lower substrate 19 of the touch panel in order to rework them. The adhesive strength of the transparent adhesive layer 25 is 10,000 gf / If it exceeds in, since it is difficult to remove it, it is preferable to form it to have an adhesive force of at least 10,000 gf / in or less. For reference, when it is configured to have an adhesive force of less than 50 gf / in, the transparent adhesive layer 25 may have a problem that the upper contact electrode formed on the upper substrate 11 of the touch panel and the transparent insulating adhesive film fall during frequent touches. The composition may be configured to have an adhesive force in a range of 50 gf / in to 10,000 gf / in.

Next, the transparent adhesive layer 40 of the present invention, unlike the transparent adhesive layer 25 requires a strong adhesion to the adhesive force rather than elasticity and flexibility. This is because the transparent fixing layer 40 corresponds to an element for fixing the conductive balls 30 on the substrate so that the conductive ball 30 does not flow in response to the user's pressurization.

Therefore, if a polymer resin is used as the transparent fixing agent, it is preferable to use a polymer resin having relatively better adhesive properties, or to add an adhesion enhancer to enhance adhesion or to increase the blending ratio of subcomponent materials that control the adhesion. Do.

In addition, unlike the transparent adhesive layer 25 configured to have a Shore hardness of "30 or less", the transparent fixing layer 40 may be formed to have a Shore Hardness of "30 or more". This is because, in the case of the transparent fixing layer 40, fixing of the conductive ball 30 is more important than flexibility.

As described above, the conductive ball 30 of the present invention is provided in a form in which some volume is included in the transparent fixing layer 40 and the other volume is included in the transparent adhesive layer 25, the spacer 27 is transparent fixing Located on the upper surface of the layer 40, the entire volume is provided in a mixed form inside the transparent adhesive layer 25.

Therefore, the spacer 27 of the present invention is a liquid transparent adhesive containing a plurality of spacers 27, after mixing a plurality of spacers 27 to the liquid transparent adhesive for forming the transparent adhesive layer 25, and mixed. By stirring the mixture evenly so that the spacers 27 can be sufficiently dispersed at a predetermined interval therebetween. When the mixing and stirring process of the spacer 27 and the liquid adhesive is completed, it is applied on the transparent fixing layer 40 laminated on the lower substrate 19 and solidified to form a coating layer. The solidifying of the transparent adhesive is UV A curing or thermosetting method may be used, and as the thermosetting method, far-infrared heating may be used.

In addition, as described above, the spacer 27 is mixed with the liquid transparent adhesive to form a laminate, and the spacer 27 and the conductive ball 30 are mixed together in a liquid transparent adhesive and mixed with the lower substrate. It is a matter of course that it can also be configured in the form of a "transparent fixing layer in which the conductive balls and spacers are mixed" by laminating on (19). Even in this case, the thickness of the transparent fixing layer 40 should be configured to be smaller than the diameter of the conductive ball 30. Accordingly, only a portion of the lower volume of the spacer 27 is included in the transparent fixing layer 40, and the remaining volume is The spacer part exposed on the transparent fixing layer 40 and thus exposed is provided in a form included in the transparent adhesive layer 25.

In the case of forming the transparent adhesive layer 40 through the above-described method, the step of mixing and dispersing the spacer 27 after mixing into the liquid transparent adhesive may be omitted. (25) Since the formation is completed, there is an advantage that can improve the process yield.

5 is a cross-sectional view of a touch panel with improved visibility according to a second embodiment of the present invention. The second embodiment of FIG. 5 has basically the same lamination structure and configuration as the first embodiment, but has the following differences.

That is, in the first embodiment, the conductive balls 30 are mixed and dispersed in a liquid transparent fixing agent to form a lamination in the form of “transparent fixing layer 40 in which the conductive balls 30 are partially contained”. According to the present invention, the conductive balls 31 are added to the liquid transparent fixing agent and coated on the lower substrate without mixing, and then the plurality of conductive balls 31 are randomly scattered on the applied liquid transparent fixing agent. After sprinkling, the conductive ball was configured to adhere onto the transparent fixing layer 41 by UV curing or thermosetting. According to the second embodiment, the transparent fixing layer 41 laminated on the lower substrate 19 is preferably configured to have a very thin thickness. "Very thin" means a thickness that is thinner than the first embodiment having a thickness of 25 µm or less, and the minimum thickness capable of attaching and fixing the conductive balls onto the substrate. This is different from the first embodiment in which the conductive balls are partially mixed in the transparent fixing layer. In the second embodiment, the conductive balls 31 are not included in the transparent fixing layer 41 but are present in a form attached thereto. If the transparent fixing layer 41 is made thicker than necessary, smooth conduction between the lower contact electrode 17 and the conductive ball 31 formed on the lower substrate 19 becomes difficult.

According to the same method as in the second embodiment, the process of mixing and dispersing the conductive balls in a liquid transparent fixing agent can be omitted, and the conductive balls are fixed by simply scattering the conductive balls 31 after applying the transparent fixing agent. Since the formation of the transparent fixing layer 41 is completed, there is an advantage that the process yield can be improved, but there is a disadvantage in that the fixing state of the conductive ball 31 is lowered than in the first embodiment.

6 is a cross-sectional view of a touch panel with improved visibility according to a third embodiment of the present invention. The third embodiment of FIG. 6 has basically the same laminated structure and configuration as the first embodiment, but has the following differences.

That is, in the first exemplary embodiment, the liquid transparent fixing agent in which the conductive balls 30 are mixed is formed on the entire surface of the lower substrate 19, but in the third exemplary embodiment, the conductive balls 32 are formed as shown in FIG. This mixed liquid transparent fixing agent was applied only to a necessary area to form a "transparent fixing layer 42 to which the conductive balls 32 are fixed." Therefore, the space between the transparent fixing layer 42 (that is, the region where the transparent fixing layer 42 is not formed) is filled by the transparent adhesive layer 25 coated on the transparent fixing layer 42.

7 is a cross-sectional view of a touch panel with improved visibility according to a fourth embodiment of the present invention. As in the third embodiment, the fourth embodiment has a structure in which a transparent fixing layer is applied to only a necessary area and laminated in the same manner as in the third embodiment, and the conductive ball 33 is not mixed with the liquid transparent fixing agent in advance. It has a structure formed by applying only the fixing agent to the required area and then scattering and curing the conductive balls 33 thereon.

8 is a cross-sectional view of a touch panel with improved visibility according to a fifth embodiment of the present invention. The fifth embodiment is formed by the same manufacturing method as the first embodiment, except that the first embodiment in which the transparent fixing layer 40 in which the conductive balls 30 are mixed is laminated on the lower substrate 19. There is a difference in having a structure in which the transparent fixing layer 44 in which the conductive balls 34 are mixed is laminated on the upper substrate 11.

9 is a cross-sectional view of a touch panel with improved visibility according to a sixth embodiment of the present invention. The sixth embodiment is formed by the same manufacturing method as the second embodiment, except that the transparent adhesive is applied to the lower substrate 19 and then the conductive ball is scattered thereon, unlike the second embodiment. After coating on the upper substrate 11, the conductive ball 35 is scattered thereon, so that the transparent fixing layer 45 is laminated on the upper substrate 11, and the conductive ball 35 is attached thereto. There is a difference in points.

10 is a cross-sectional view of a touch panel with improved visibility according to a seventh embodiment of the present invention. The seventh embodiment is formed by the same manufacturing method as the third embodiment, except that the transparent fixing layer 42 in which the conductive balls 32 are mixed is laminated only on the required area of the lower substrate 19. Unlike the example, there is a difference in that the transparent fixing layer 46 in which the conductive balls 36 are mixed is laminated on only the required area of the upper substrate 11.

11 is a cross-sectional view of a touch panel with improved visibility according to an eighth embodiment of the present invention. The eighth embodiment is formed by the same manufacturing method as the fourth embodiment, except that the transparent fixing agent 43 is applied only on the required area of the lower substrate 19, and then the conductive balls 33 are scattered thereon. Unlike the fourth embodiment, the transparent fixing layer 47 is laminated on the upper substrate 11 by applying the transparent fixing agent only on the required area of the upper substrate 11 and then scattering the conductive balls 37 thereon. There is a difference in that the conductive ball 37 has a structure attached thereto.

3 is a process flowchart showing a manufacturing process sequence of the touch panel with improved visibility according to the present invention. Hereinafter, a method of manufacturing a touch panel having improved visibility according to a first embodiment of the present invention will be described with reference to FIG. 3.

Step 1-1. Upper board manufacturing (S10)

After the transparent upper substrate 11 is washed and prepared, the upper contact electrode 13 is patterned on one surface, and the electrode wiring Ag is printed and then cured.

Step 1-2. Lower substrate manufacturing (S11)

After the transparent lower substrate 19 is washed and prepared, the lower contact electrode 17 is patterned on one surface, and then the electrode wiring Ag is printed and then cured.

Step 2. Form a transparent fixing layer to which the conductive ball is fixed (S20)

The transparent fixing layer to which the conductive balls of step 2 are fixed may be formed in two ways.

In the first case, as shown in FIG. 4, a plurality of conductive balls 30 are mixed with a liquid transparent fixing agent and stirred, and then coated on one surface of the lower substrate 19 on which the lower contact electrode 17 is formed and then solidified. Some volumes of the ball 30 are laminated to form the transparent fixing layer 40 mixed therein.

In the second case, as shown in FIG. 5, after the conductive ball is not mixed with the liquid transparent adhesive, the conductive balls are applied to the lower substrate, and then the conductive balls 31 are randomly scattered in the applied liquid transparent adhesive. By sprinkling and curing, the conductive balls are manufactured to adhere onto the transparent fixing layer 41.

Step 3. Form a transparent adhesive layer mixed with the spacer (S30)

After the plurality of spacers 27 are mixed with the liquid transparent adhesive and stirred, the conductive balls 30 are applied onto the transparent fixing layer 40 to which the conductive balls 30 are fixed, and then solidified. The conductive particles are not buried in the transparent fixing layer 40. The remaining volume of the ball and the transparent adhesive layer 25 in which the spacers 27 are mixed are laminated to form.

In this case, the series of processes may be performed in a roll or sheet state. That is, by curing the transparent adhesive, the upper substrate 11 is bonded (S40), or the upper substrate 11 is bonded (S40), and then the transparent adhesive is cured, thereby the upper substrate 11 and the lower substrate 19 Manufacturing of the touch panel in which the transparent adhesive layer 40 and the transparent adhesive layer 25 are laminated between the layers is completed.

While the preferred embodiments of the present invention have been described and illustrated above using specific terms, such terms are used only for the purpose of clarifying the invention, and it is to be understood that the embodiment It will be obvious that various changes and modifications can be made without departing from the spirit and scope of the invention. Such modified embodiments should not be understood individually from the spirit and scope of the present invention, but should be regarded as being within the scope of the claims of the present invention.

11: upper substrate 13: upper contact electrode
17: lower contact electrode 19: lower substrate
25 transparent adhesive layer 27 spacer
30 to 37: conductive ball 40 to 47: transparent fixing layer
110, 210: diffuse reflection 200: internal light

Claims

delete

In the resistive touch panel having an upper substrate having an upper contact electrode and a lower substrate having a lower contact electrode,
A transparent fixing layer having conductive balls fixed to the upper contact electrode or the lower contact electrode laminated on one of the contact electrodes;
A transparent adhesive layer laminated on the transparent fixing layer to which the conductive balls are fixed;
The other one of the non-selected contact electrode is adhered to the transparent adhesive layer, the upper substrate and the lower substrate is bonded,
The conductive ball is fixed to the transparent fixing layer in a form in which at least a portion of the volume inside the transparent fixing layer is mixed or fixed to the transparent fixing layer attached to the transparent fixing layer is improved visibility Touch panel.

The method of claim 3,
The transparent adhesive layer is further provided with a mixture of spacers, the diameter of the spacer is equal to or less than the thickness of the transparent adhesive layer, the diameter of the conductive ball is characterized in that the provided smaller than the diameter of the spacer Touch panel with improved visibility.

The method according to claim 3 or 4,
The transparent fixing layer is
Touch panel with improved visibility, characterized in that formed of a transparent fixing agent having a light transmittance of 80% or more and adhesive strength of 50 gf / in.

The method of claim 5,
The transparent fixing agent is a touch panel improved visibility, characterized in that made of at least one material selected from acrylic copolymers, silicone elastomers and epoxy copolymers cured by UV curing or thermosetting.

The method of claim 5,
The transparent fixing agent is a touch panel with improved visibility, characterized in that the conductive polymer resin containing a pedo (PEDOT).

The method according to claim 3 or 4,
The refractive index of the transparent fixing layer is the same as the refractive index of the transparent adhesive layer or the touch panel, characterized in that the difference within the range of less than 0.1.

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As a method of manufacturing a resistive touch panel,
A first step of manufacturing an upper substrate having an upper contact electrode formed on one surface and a lower substrate having a lower contact electrode formed on one surface;
A second step of laminating a transparent fixing layer having conductive balls fixed to an upper portion of any one selected from the upper contact electrode and the lower contact electrode;
A third step of stacking a transparent adhesive layer mixed with spacers on the transparent fixing layer to which the conductive balls are fixed; And
And a fourth step of bonding the remaining contact electrode not selected in the second step on the transparent adhesive layer.
In the second step, a plurality of conductive balls are mixed with a liquid transparent fixing agent, stirred, applied to the selected contact electrode, and then solidified to form a transparent fixing layer having a portion of the conductive balls mixed inside. Touch panel manufacturing method characterized in that the improved visibility.

As a method of manufacturing a resistive touch panel,
A first step of manufacturing an upper substrate having an upper contact electrode formed on one surface and a lower substrate having a lower contact electrode formed on one surface;
A second step of laminating a transparent fixing layer having conductive balls fixed to an upper portion of any one selected from the upper contact electrode and the lower contact electrode;
A third step of stacking a transparent adhesive layer mixed with spacers on the transparent fixing layer to which the conductive balls are fixed; And
And a fourth step of bonding the remaining contact electrode not selected in the second step on the transparent adhesive layer.
In the second step, the conductive balls are transparently fixed by applying the conductive balls onto the selected contact electrode in a state where the conductive balls are not mixed with the liquid transparent fixing agent, and then scattering and curing a plurality of conductive balls in the applied liquid transparent fixing agent. Touch panel manufacturing method with improved visibility, characterized in that formed in a structure attached to the upper layer.

The method according to claim 3 or 4,
The transparent fixing layer is a touch panel improved visibility, characterized in that formed to have a thickness at least smaller than the diameter of the conductive ball.